Table 1.

Baseline characteristics of the 90-d study population by cohort year and overall

Baseline CharacteristicsCohort YearTotal (n=23,549)
2006–2008 (n=7586)2009–2011 (n=7286)2012–2015 (n=8677)
Age (yr), median (IQR)63 (52–74)63 (53–74)64 (54–74)64 (53–74)
Race, n (%)
 White4580 (60)4532 (62)5235 (60)14,347 (61)
 Black2681 (35)2440 (34)3001 (35)8122 (35)
 Other325 (4)314 (4)441 (5)1080 (5)
Sex, n (%)
 Male4195 (55)4201 (58)4982 (57)13,378 (57)
 Female3391 (45)3085 (42)3695 (43)10,171 (43)
Hispanic ethnicity, n (%)423 (6)478 (7)513 (6)1414 (6)
Insurance status (90 d), n (%)
 Total subsidy335 (4)332 (5)600 (7)1267 (5)
 Moderate subsidy1571 (21)1532 (21)1137 (13)4240 (18)
 Small or no subsidy5049 (67)4756 (65)6096 (70)15,901 (68)
 Other/unknown615 (8)654 (9)834 (10)2103 (9)
Primary cause of kidney failure, n (%)
 Diabetes3591 (50)3358 (48)4142 (50)11,091 (49)
 Hypertension2099 (29)2035 (29)2463 (29)6597 (29)
 GN668 (9)614 (9)694 (8)1976 (9)
 Other cause890 (12)938 (14)1076 (13)2904 (13)
Comorbidity index, median (IQR)3 (1–5)3 (1–5)3 (1–5)3 (1–5)
 Atherosclerotic heart disease, n (%)1801 (24)1672 (23)1757 (20)5230 (22)
 Congestive heart failure, n (%)2581 (34)2321 (32)2766 (32)7668 (33)
 Cerebrovascular accident/transient, n (%)897 (12)845 (12)910 (11)2652 (11)
 Peripheral vascular disease, n (%)1143 (15)1016 (14)1187 (14)3346 (14)
 Other cardiac, n (%)1601 (21)1627 (22)2196 (25)5424 (23)
 Chronic obstructive pulmonary disease, n (%)817 (11)786 (11)1104 (13)2707 (12)
 Cancer, n (%)656 (9)656 (9)786 (9)2098 (9)
 Diabetes mellitus, n (%)3911 (52)3808 (52)4690 (54)12,409 (53)
 Inability to ambulate, n (%)537 (7)501 (7)671 (8)1709 (7)
Parathyroid hormone at 90 d (pg/ml), median (IQR)181 (101–303)242 (135–416)310 (165–507)239 (130–426)
 <150 pg/ml, n (%)2937 (41)2018 (28)1883 (22)6838 (30)
 150–299 pg/ml, n (%)2423 (34)2319 (32)2283 (27)7025 (31)
 300–599 pg/ml, n (%)1480 (21)2192 (31)3019 (35)6691 (29)
 ≥600 pg/ml, n (%)363 (5)622 (8)1416 (17)2401 (11)
Parathyroid hormone at 12 mo, n (%)
 <150 pg/ml1834 (32)1286 (23)981 (18)4101 (24)
 150–299 pg/ml2207 (38)1857 (33)1603 (30)5667 (34)
 300–599 pg/ml1479 (26)2103 (37)2014 (38)5596 (33)
 ≥600 pg/ml239 (4)420 (7)761 (14)1420 (9)
Phosphate at 90 d (mg/dl), median (IQR)5.1 (4.2–6.3)5.2 (4.3–6.3)5.1 (4.3–6.2)5.1 (4.3–6.2)
Albumin-corrected calcium at 90 d (mg/dl), median (IQR)9.3 (8.9–9.7)9.3 (8.9–9.7)9.3 (8.9–9.7)9.3 (8.9–9.7)
Albumin at 90 d (g/dl), median (IQR)3.6 (3.3–3.9)3.6 (3.3–3.9)3.7 (3.4–4.0)3.6 (3.3–3.9)
Dialysis time at 90 d (min/wk), median (IQR)630 (585–720)630 (585–720)675 (630–720)630 (630–720)
Kt/V at 90 d, median (IQR)1.5 (1.4–1.7)1.5 (1.4–1.7)1.5 (1.4–1.7)1.5 (1.4–1.7)
Dialysate calcium at 90 d, n (%)a
 <2.00 mEq/L98 (1)87 (1)60 (1)245 (1)
 2.00–2.24 mEq/L624 (8)919 (13)1214 (14)2757 (12)
 2.25–2.44 mEq/L78 (1)94 (1)320 (4)492 (2)
 2.45–2.94 mEq/L5851 (78)5665 (78)6595 (76)18,111 (77)
 ≥3.00 mEq/L884 (12)510 (7)469 (6)1863 (8)
  • IQR, interquartile range.

  • a Common dialysate calcium values are 2.0, 2.25, 2.5, 3.0, and 3.5 mEq/L.